"Ask not what your country can do for you," U.S. President John F. Kennedy exhorted in his 1961 inaugural address. "Ask what you can do for your country." But what if JFK was wrong? New research by London School of Economics professor Oriana Bandiera, Harvard Business School associate professor Nava Ashraf, and Harvard Ph.D. candidate Scott Lee points to the possibility that maybe those drawn into government through selfish motives — those very people asking just what their country can do for them — may well make the better public servants.

Bandiera tracked the performance of two groups of community health workers in rural Zambia over the past year. The first group was composed of people recruited for the characteristics we traditionally think of as ideal in civil servants — devotion to the community, a desire to serve — while the second group was recruited via a campaign designed to appeal to ambitious candidates, lured by promises of training and career opportunities.

The ladder-climbers, it turned out, were more skilled and outperformed the do-gooders in areas ranging from household visits to community mobilization.

A lot of research on how to motivate civil servants tends to treat career ambition and community spirit as two drives that operate at cross-purposes, says Bandiera. But having conducted surveys of both groups, she found that the ladder-climbers were still driven by a desire to improve community well-being — they just wanted a career boost in the process.

Bandiera is still waiting to see how the two groups vary when it comes to job retention, but for now, the Zambian Ministry of Health has been so convinced by the research that it has changed its strategy on recruitment for community health work. If you want the job done right, it seems, take the Type A striver.